tdf#127423: Allow disabling default features in Font Features dialog

In OpenType fonts we have no way if detecting what features are on by
default and what not (short of hard-coding this, since HarfBuzz has no
API of giving us this information, and it is also not a fixed set
per-font, depends also on the text being shaped).

The dialog currently does not differentiate between a disabled feature
and unset feature. To make this distinction, feature value is now signed
and negative value means the feature is unset (i.e. the default is
used), and the checkbox is now a try state one to reflect this.

Change-Id: Iba5d13f02610e7b761677acc19872788c72afde1
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/138729
Tested-by: Jenkins
Reviewed-by: Tomaž Vajngerl <quikee@gmail.com>

0 files changed, 0 insertions, 0 deletions